1 /*
2 * Licensed to the Apache Software Foundation (ASF) under one or more
3 * contributor license agreements. See the NOTICE file distributed with
4 * this work for additional information regarding copyright ownership.
5 * The ASF licenses this file to You under the Apache License, Version 2.0
6 * (the "License"); you may not use this file except in compliance with
7 * the License. You may obtain a copy of the License at
8 *
9 * http://www.apache.org/licenses/LICENSE-2.0
10 *
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
16 */
17 package org.apache.commons.jxpath.ri.compiler;
18
19 import org.apache.commons.jxpath.ri.EvalContext;
20 import org.apache.commons.jxpath.ri.InfoSetUtil;
21
22 /**
23 * A compile tree element containing a constant number or string.
24 *
25 * @author Dmitri Plotnikov
26 * @version $Revision: 652845 $ $Date: 2008-05-02 13:46:46 -0400 (Fri, 02 May 2008) $
27 */
28 public class Constant extends Expression {
29
30 private Object value;
31
32 /**
33 * Create a new Constant.
34 * @param number constant
35 */
36 public Constant(Number number) {
37 this.value = number;
38 }
39
40 /**
41 * Create a new Constant.
42 * @param string constant
43 */
44 public Constant(String string) {
45 this.value = string;
46 }
47
48 public Object compute(EvalContext context) {
49 return value;
50 }
51
52 public Object computeValue(EvalContext context) {
53 return value;
54 }
55
56 /**
57 * Returns false
58 * @return false
59 */
60 public boolean isContextDependent() {
61 return false;
62 }
63
64 /**
65 * Returns false
66 * @return false
67 */
68 public boolean computeContextDependent() {
69 return false;
70 }
71
72 public String toString() {
73 if (value instanceof Number) {
74 return InfoSetUtil.stringValue(value);
75 }
76 return "'" + value + "'";
77 }
78 }